IP Case Law Analysis

Claim Preamble May Limit Scope

January 13, 2014

Be prudent when including description in a claim’s preamble because the description may limit the scope of the claim.

Be cautious when using the terms “invention” and “preferred” in the specification, since the embodiments described by these terms may be interpreted as being important or essential features and may limit claim scope.

Overview

The U.S. Court of Appeals for the Federal Circuit (Federal Circuit) confirmed in Proveris Corp. v. Innovasystems, Inc. that the preamble of a claim may be properly construed as importing a limitation into the claim when the preamble recites particular structures or steps that are highlighted as important by the specification.

Case Background

The case involved a contempt order entered by the district court against Innovasystems for manufacturing and selling a device that infringed a patent owned by Proveris. In its appeal to the Federal Circuit, Innovasystems argued that its device did not infringe Proveris’ patent because its device did not meet the features described in the preamble of Proveris’ claim.

The issue at hand was when the preamble of a claim can import a limitation into the claim.

In this case, the specification of Proveris’ patent described a particular inventive concept as being “preferable” and an advantage that the “invention” provides. The Federal Circuit viewed these statements as highlighting the importance of the inventive concept. Additionally, the description in the preamble of the claim at issue was the only reference in any independent claim of the patent to this inventive concept. The Federal Circuit stated that this fact alone is likely sufficient to support a conclusion that the preamble is limiting.

Takeaways

Be prudent when including description in the preamble of a claim, because the preamble may be construed as importing a limitation into the claim. This may particularly be the case when the description in the preamble is the only reference in any independent claim of the patent application to an inventive concept that the specification highlights as being important.

When determining whether an inventive concept is highlighted as important in the specification, a court may look for terms such as “preferable” and “invention” to describe the concept. Therefore, caution should be exercised when using these terms in the specification.